A grader assembly and vehicle

ABSTRACT

The present invention relates to a grading assembly, a grader vehicle and method for maintaining a dirt or gravel road. The grader assembly is adapted for use with a water truck or truck having water dispersal means to shape and maintain a camber or a crown of a dirt or gravel road. The assembly includes a grading device carried by the truck for shaping and maintaining the camber or the crown of the dirt or gravel road.

TECHNICAL FIELD

The present invention relates to a grading assembly and vehicle for grading a surface of a dirt or gravel road, in particular to a grading assembly and vehicle for shaping and maintaining a camber or a crown of a dirt or gravel road.

BACKGROUND

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

Dirt and gravel roads are prone to deteriorate over time, especially after wet periods and when accommodating increased traffic. Water, if not properly drained from a surface of a dirt or gravel road, can cause pot holes or ruts in the surface. Likewise, wheel motion from increased traffic can displace road material from the surface resulting in rutting and reduced water run-off from the road surface. Both issues if left unchecked can result in the destruction of dirt and gravel roads.

Consequently, both dirt and gravel roads require regular maintenance in the form of grading to: (1) push road material back into shape (i.e., fill in any depressions, e.g., pot holes, wheel ruts, etc.); (2) smooth the surface of the dirt or gravel road in the direction of travel (e.g., removal or reduction of road corrugations); and (3) maintain the road's crown or camber used to facilitate drainage of water from the road's surface. This is typically achieved through multiple passages of a grader over the dirt or gravel road.

The grading process of a dirt or gravel road optimally includes the addition of a controlled quantity of water to the road material to facilitate movement, shaping and compaction of the road material, and compaction of the road material once the surface has been graded to increase the durability and load bearing properties of the dirt or gravel road.

As such, the process of grading typically requires, in addition to a grader, at least a water truck and, in some cases, a compaction roller as well. While this may not be a problem in areas reasonably close to commercial centres, which have access to all three types of vehicles, it is a problem in isolated areas.

Of course, there are also the costs associated with contracting all three vehicles to carry out regular dirt or gravel road maintenance. These costs may be considerable, particularly if regular maintenance is required or the dirt or gravel road is located in an isolated area.

Embodiments of the present invention provide a grader assembly or grader vehicle, which eliminates the need for more than one vehicle in the maintenance of dirt or gravel roads.

SUMMARY OF INVENTION

According to one aspect of the present invention, there is provided a grading assembly adapted for use with a water truck or truck having water dispersal means to shape and maintain a camber or a crown of a dirt or gravel road, said assembly including:

a grading device carried by the truck for shaping and maintaining the camber or the crown of the dirt or gravel road.

Advantageously, the grading assembly when carried by the truck provides all three requirements for optimal re-grading of a dirt or gravel road, namely: a grader by way of the grading device, and dispersal of water and compaction by way of the water dispersal means. The compaction may be achieved by the passage of the truck (additionally weighted down by a load of water) over the surface of the dirt or gravel road. Consequently, the grading assembly eliminates the need for three separate construction vehicles and the associated costs. Additionally, by eliminating the need for three separate vehicles, the grading assembly of the present invention provides a safer working environment by reducing construction traffic on the dirt or gravel road being graded.

The truck may be a vehicle of any shape or size having a water reservoir suitably adapted to carry a volume of water and having water dispersal means. The water dispersal means may be of any suitable form. For example, water may be dispersed by gravity, for instance by a gravity drip bar, or water may be dispersed in a pressurised manner. Typically, the water dispersal means may include one or more dispersal nozzles equipped with mechanics to pump water from the water reservoir and disperse the water on to the surface of a road.

The water dispersal means may be located in any suitable location on the water truck, such as the front, side, middle or rear of the truck. In one embodiment, the water dispersal means in the form of one or more dispersal nozzles may be situated at or near the rear of the truck enabling water to be ejected in a controlled and specified capacity behind the truck preparing the surface of the dirt or gravel road for a return passage of the truck. In preferred embodiments, the water dispersal means in the form of one or more dispersal nozzles may be located immediately in front of the grading device.

In addition to the compaction of the surface of the dirt or gravel road provided by passage of the truck, the assembly may further include a compacting device configured to facilitate in the compaction of the surface of the dirt or gravel road. The compacting device may be of any size, shape and construction and formed of any material or materials suitably adapted to compact the surface of the dirt or gravel road.

For example, in one form the compacting device may be in the form of at least one roller carried at or near the rear of the truck for rolling over the surface of the dirt or gravel road passed over by the truck. The roller, preferably, may be moveable between an operational position in which the roller may roll over the surface and a raised stowage position in which the roller is held clear of the surface. The roller may be moved between positions by manual means, e.g., by hand, or may be powered between positions by an electric, hydraulic, pneumatic or internal combustion motor.

In another form the compacting device may be in the form of at least one vibrating plate carried at or near the rear of the truck and configured to be pulled or dragged over the surface of the dirt or gravel road passed over by the truck. The vibrating plate may, in use, provide a vibrating motion, which, when engaged with the surface of the road, may vibrate the road material and thereby consolidate and compact the surface of the dirt or gravel road. The vibrating plate may be powered by any suitable power source and may be hydraulically driven, electrically driven or driven by an internal combustion engine.

The vibrating plate, as with the roller, may preferably be moveable between an operational position in which the vibrating plate may engage with the surface of the dirt or gravel road and a raised stowage position in which the vibrating plate is held clear of the surface. Again, as with the roller, the vibrating plate may be moved between positions by manual means, e.g., by hand, or may be powered between positions by an electric, hydraulic, pneumatic or internal composition motor.

The grading device of the present invention may be of any size, shape and construction and formed from any material or materials suitably adapted to shape and maintain the camber or the crown of a dirt or gravel road. In its simplest form, the grading device may be any device capable of smoothing the surface of the dirt or gravel road in a direction of travel of the truck, move road material in the direction of travel (e.g., to fill pot holes and ruts), and also, preferably, in a direction substantially perpendicular to the direction of travel (e.g., to facilitate in the maintenance and re-formation of a dirt or gravel road's crown or camber).

Typically, the grading device may be formed from metal, preferably steel, more preferably hardened steel.

The grading device may be carried by an underside of the truck in any suitable location such that the device may engage with the surface of the dirt or gravel road. For instance, the grading device may be coupled to a front or rear end of the truck, or a position therebetween.

Preferably, to facilitate in the removal or reduction of corrugations in dirt or gravel roads, the grading device may be positioned between front and rear axles of the truck.

For example, if the truck is a semi-trailer truck, the grading device may be positioned between axles of the prime mover or truck tractor and axles of the trailer.

In one embodiment, the grading device may be in the form of a grader blade as is found in conventional grader vehicles. The grader blade may have an upper end that is either directly or indirectly coupled to the underside of the truck and a lower ground engaging edge configured to move and smooth road material in a direction of travel of the truck.

In another embodiment, the grading device may be in the form of a drag for dragging along the surface of the dirt or gravel road to grade the surface. The drag may include an upper substantially horizontal panel coupled either directly or indirectly to the underside of the truck and at least two ground engaging rails extending downwardly from the panel. The at least two rails may extend substantially along opposite sides of the drag in the direction of travel. The drag may further include at least one grading blade extending downwardly from the panel in any suitable arrangement for shaping and maintaining the camber or the crown of the road. In use, the at least one grading blade may move and smooth road material to facilitate in maintaining and shaping a road's crown or camber.

In another embodiment, the grading device, again in the form of a drag, may be operationally associated or coupled with a powered drum that has rows of mixing blades or paddles as is found in a soil stabilizer. In use, the rows of mixing blades or paddles may mix road material with water to facilitate in the movement, shaping and compaction of the road material. Preferably, a binding agent may also be mixed in with the road material and water. The binding agent may include any suitable binding agent, such as, e.g., Portland cement or lime.

In yet another embodiment, the grading device, again in the form of a drag, may include an upper substantially horizontal panel coupled either directly or indirectly to the underside of the truck and a plurality of scraper blades extending downwardly from the panel for scraping and thereby shaping and maintaining the camber or the crown of the road. The scraper blades may be arranged on the panel in any suitable arrangement. Preferably, however, each scraper blade may extend across a length of the panel and be arranged substantially parallel relative to other scraper blades.

In a further embodiment, the grading device in the form of a drag may include a first portion of scrapers configured to, in use, move road material sideways relative to the direction of travel, and a second portion of scrapers configured to, in use, smooth road material moved sideways by the first portion (e.g., to collectively facilitate in maintaining and shaping a road's crown or camber).

The first portion of scrapers may be arranged parallel to one another and at an angle relative to the direction of travel of the truck to facilitate in moving the road material sideways relative to the direction of travel.

The second portion of scrapers may be arranged substantially alongside the first portion on the panel to receive the road material moved. Preferably, the second portion of scrapers, like the first portion of scrapers, may be arranged parallel to one another, but may partially extend across the panel in a direction substantially perpendicular to the direction of travel. Additionally, the scrapers of the second portion may each extend downwardly from the panel at an angle away from the direction of travel to facilitate in smoothing the road material moved by the first portion of scrapers.

As mentioned above, the grading device of the present invention may be coupled either directly or indirectly to the underside of the truck, preferably indirectly via an adjustable carriage assembly.

By way of the adjustable carriage assembly, any one of inclination (i.e., tilt), orientation and pitch (i.e., side to side pivotal movement relative to the direction of travel) of the grading device may be adjustable to, again, facilitate in the shaping of road material in the grading process.

Typically, however, regardless as to whether the grading device is directly or indirectly coupled to the truck, the grading device may be moveable between an operational position in which the grading device may engage with the surface of the dirt or gravel road and a stowage position in which the grading device may be held clear of the surface of the dirt or gravel road. The grading device may be moved between the positions by any suitable means.

For example, the grading device may be moved between the positions by manual means, e.g., by hand, or may be powered between the positions by an electric, hydraulic, pneumatic or internal combustion motor.

For example, the grading device may be moved between positions by a cable and an electric winch.

For example, the grading device may be moved between positions using one or more ram-type actuators. Advantageously, this would allow the grading device to be forcibly applied against the surface of the road. The one or more ram-type actuators may include a hydraulic ram, a pneumatic ram or a combination thereof.

In one embodiment, the adjustable carriage assembly may be in the form of a planar linkage mechanism, preferably a parallelogram linkage mechanism. The parallelogram linkage mechanism may have at least two coupling arms that may be pivotally coupled to the underside of the truck and to an upper portion of the grading device to facilitate movement of the grading device between the operational and stowage positions. This may allow the grading device to be carried and moved in a substantially parallel plane to the underside of the truck and to the surface of the dirt or gravel road. In this embodiment, the grading device may be coupled to the at least two coupling arms such that the grading device is capable of side to side pivotal movement relative to the direction of travel, preferably such that the pitch of the grading device may be adjusted. In this embodiment, the orientation of the grading device may be adjustable relative to the adjustable carriage assembly or not.

In another embodiment, the adjustable carriage assembly may include a coupling arm that may be pivotally coupled to the underside of the truck and to an upper portion of the grading device to facilitate in movement of the grading device between the operational and stowage positions.

The grading device may further be rotationally coupled to the coupling arm such that the orientation of the grading device relative to the direction of travel may be adjustable. In this regard, the assembly may further include a rotating mechanism for rotating the grading device relative to the coupling arm to thereby adjust the orientation of the grading device.

The rotating mechanism may be of any suitable form. Typically, however, the rotating mechanism may be operatively associated with the upper portion of the grading device and have at least one rotating member extending outwards from the rotating mechanism in a direction substantially parallel with the upper portion of the grading device. The at least one rotating member may be rotatable around a central axis and be configured to be operable with the upper portion of the grading device to rotate the grading device around its vertical axis relative to the coupling arm.

Preferably, the rotating mechanism may include a further rotating member extending in an opposite direction to the at least one rotating member. The further rotating member may be configured to be rotatable around its central axis in an opposite direction to the direction of rotation of the at least one rotating member to facilitate rotation of the grading device around its vertical axis.

Each rotating member may further include a gripping member for gripping with the upper portion of the grading device and rotating the grading device. The gripping member may be positioned at any suitable location along a length of each rotating member. Preferably, the gripping member may be located at or near an end of each rotating member, more preferably at a distal end of each rotating member.

The rotating mechanism may be manually driven, e.g., by hand, or be driven by an electric, hydraulic, pneumatic or internal combustion motor.

In yet a further embodiment, the adjustable carriage assembly may include at least one chain, preferably at least two chains, coupled to an underside of the truck and to an upper portion of the grading device. The at least one chain may be coupled to the upper portion together with a cable and a moveable pulley associated with cable. The cable may be associated with a winch and, preferably at least one fixed pulley, coupled to the underside of the truck. In this arrangement, the grading device may be moved between the operational position and the stowage position in a linear translational movement by action of the winch winding in or letting out the cable.

The at least one chain, the cable and the pulley may be removably coupled to the upper portion of the grading device so that the orientation of the grading device may be manually adjusted. The upper portion of the grading device may include a plurality of apertures, each aperture configured to receive a coupler to couple any one of the at least one chain, the cable and the pulley to the upper portion such that, in use, an operator may manually uncouple any one of the at least one chain, the cable and the pulley from the upper portion and then re-couple the uncoupled item to a different aperture to adjust the orientation of the grading device.

The assembly may further include one or more video cameras positioned on or near the grading assembly to allow the operator to monitor the grading process from the cab of the truck. The one or more video cameras may further assist the operator in adjusting any one of the inclination, orientation and pitch of the grading device during operation. The video footage may be transmitted either by cable or wirelessly to one or more monitors located in the cab of the truck.

According to another aspect of the present invention, there is provided a grader vehicle for maintenance of a dirt or gravel road, said vehicle including:

a grading device for shaping and maintain a camber or a crown of the dirt or gravel road; and

water dispersal means for dispersing water on to the dirt or gravel road to facilitate in the shaping and maintaining of the camber or the crown of the dirt or gravel road.

The vehicle preferably includes a prime mover or truck tractor and a trailer hitched to the prime mover or truck tractor.

In a preferred embodiment:

the grading device of the vehicle may be carried by an underside of the trailer such that the grading device may engage with the surface of the dirt or gravel road and may be positioned between the axles of the prime mover or truck tractor and the trailer; and

the water dispersal means may be attached in front of the grading device such that water is dispersed on to the surface of the dirt or gravel road in preparation for passage of the grading device.

The vehicle, preferably the trailer, may further include a water reservoir for carrying a volume of water to be dispersed by the water dispersal means.

The water dispersal means may be of any size, shape and form suitably adapted to disperse water. The water may be dispersed by gravity, e.g., by a gravity drip bar, or may be dispersed in a pressurised manner. Preferably, the water dispersal means may include one or more dispersal nozzles equipped with mechanics to pump water from the water reservoir and disperse the water on to the surface of the dirt or gravel road.

The water dispersal means may be located in any suitable location on the vehicle, such as the front, side, in the middle or rear of the vehicle. Typically, however, the water dispersal means in the form of one or more dispersal nozzles may be located on the trailer in front of the grading device enabling water to be dispersed in a controlled and specified capacity.

In some embodiments, the vehicle may include more than one trailer hitched in series to the prime mover or tractor (e.g. like a road train). Each trailer may include a grading device and water dispersal means.

According to yet another aspect of the present invention, there is provided a method of maintaining a dirt or gravel road with a grading assembly attached to a water truck or truck having water dispersal means, said method including:

shaping and maintaining a camber or a crown of the dirt or gravel road with a grading device carried by the truck.

The method may include one or more features or characteristics of the grading assembly or grader vehicle as described hereinbefore.

For example, the method may further include compacting the surface of the dirt or gravel road by passage of the truck.

Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention.

BRIEF DESCRIPTION OF DRAWINGS

Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of Invention in any way. The Detailed Description will make reference to a number of drawings as follows:

FIG. 1 is a perspective view of a grader assembly according to an embodiment of the present invention in an operational mode;

FIG. 2 is a perspective view of the grader assembly shown in FIG. 1 in a non-operational mode;

FIG. 3 is an exploded perspective view of a grading device and associated adjustable carriage assembly of the grading assembly as shown in FIGS. 1 and 2;

FIG. 4 is a perspective view of a grader assembly according to another embodiment of the present invention in an operational mode;

FIG. 5 is a perspective view of the grader assembly shown in FIG. 4 in a non-operational mode;

FIG. 6 is an exploded perspective view of a grading device and associated adjustable carriage assembly of the grading assembly as shown in FIGS. 4 and 5;

FIG. 7 is a bottom view of the grading device as shown in FIGS. 4 to 6;

FIG. 8 is a perspective view of a grader assembly according to another embodiment of the present invention in an operational mode;

FIG. 9 is a perspective view of the grader assembly shown in FIG. 8 in a non-operational mode;

FIG. 10 is an exploded perspective view of the grading device and associated adjustable carriage assembly as shown in FIGS. 8 and 9;

FIG. 11 is a perspective view of a grader assembly according to another embodiment of the present invention in an operational mode;

FIG. 12 is a perspective view of the grader assembly shown in FIG. 11 in a non-operational mode;

FIG. 13 is an exploded perspective view of the grading device and associated adjustable carriage assembly as shown in FIGS. 11 and 12; and

FIGS. 14A to 14D respectively show perspective views of further embodiments of the grader assemblies shown in FIGS. 2, 5, 9 and 12.

DETAILED DESCRIPTION

FIG. 1 shows a grading assembly (100) according to an embodiment of the present invention adapted for use with a truck (110) having water dispersal nozzles (112; i.e., water dispersal means) to maintain a dirt or gravel road. The assembly (100) includes a grading device (120) carried by the truck (110) for shaping and maintaining a camber or a crown of the dirt or gravel road.

Advantageously, the grading assembly (100), when carried by the truck (110), provides all three requirements for optimal maintenance of a dirt or gravel road, namely: (i) a grader by way of the grading device (120); (ii) dispersal of water by way of the water dispersal nozzles (112) of the truck (110), and (iii) compaction also by way of the truck (110). Compaction is achieved by passage of the truck (110), additionally weighted down by a load of water, over the surface of the dirt or gravel road. As such, the grading assembly (100) eliminates the need for three separate construction vehicles (i.e., a grader, a water truck and a roller), and the associated costs. Additionally, by eliminating the need for three separate vehicles, the grader assembly (100) of the present invention provides a safer working environment by reducing construction traffic on the dirt or gravel road being re-graded.

Referring to FIG. 1, the grading device (120) is carried by an underside of the truck (110) in a position between the axles of the prime mover (114) and the axles of the trailer (116) of the truck (110). In this position, a lower end of the grading device (120), which is in the form of a grader blade, is able to engage with and grade the surface of the dirt or gravel road in the direction of travel of the truck (110).

The grading device (120) is indirectly coupled to the underside of the truck (110) via an adjustable carriage assembly in the form of a coupling mechanism (130). The coupling mechanism (130) facilitates movement of the grading device (120) between the operational position (as presently shown) in which the grading device (120) is able to engage with the surface of the dirt or gravel road, and a stowage position in which the grading device (120) is raised and held clear of the surface of the road.

As can also be seen in FIG. 1, the water dispersal nozzles (112) are located at the rear of the truck (110), enabling water to be ejected in a controlled and specified capacity behind the truck (110) in preparation for the return passage of the truck (110). As with conventional water trucks, the water dispersal nozzles (112) of the truck (110) are equipped with mechanics to pump water from the truck's water reservoir (118) and disperse the water on the surface of the road.

In addition to the compaction of the surface of the dirt or gravel road provided by the passage of the truck (110), the assembly (100) further includes a compacting roller (140; i.e., compacting device) located beneath the water dispersal nozzles (112). The compacting roller (140), which is presently shown in an operational position, is moveable to a stowage position in which the roller frame (142) and thereby the compacting roller (140) is raised and held clear of the surface of the dirt or gravel road. The roller frame (142) and the compacting roller (140) are moved between the operational and stowage positions by a cable (144) tethered to the roller frame (142) and an electric winch (146).

The grading assembly (100) further include one or more video cameras positioned on or near the grading device (120) to allow an operator to monitor the grading process from the cab of the truck (110). The one or more video cameras facilitate the operator in adjusting any one of the inclination, orientation and pitch of the grading device (120) during operation. The video footage can be transmitted either by cable or wirelessly to one or more monitors located in the cab of the truck (110).

Referring to FIG. 2, the grading device (120) and the compacting roller (140) are respectively shown in their stowage positions in which they are raised and held clear of the surface of the dirt or gravel road. By allowing the grading device (120) and compacting roller (140) to be moved to stowage positions, the grading assembly (100) of the present invention does not impede the truck (110) in transit to and from work sites. This is particularly advantageous when the work site is located in an isolated area and transit times to and from the isolated area are extensive.

Referring to FIG. 3, the grading device (120) includes a grader blade (300), which is coupled to the coupling mechanism (130) via a rotational coupling mechanism (310) that allows the grading device (120) to be rotated around its vertical axis relative to the coupling mechanism (130) to thereby adjust the orientation of the grading device (120).

The coupling mechanism (130) includes an upper part (132) and a lower part (133) connected together by a swivel joint (134). The upper part (132) is pivotally coupled to the underside of the truck via fastening plates (320). The lower part (133) is pivotally coupled to an upper part (314) of the rotational coupling mechanism (310). The swivel joint (134) advantageously enables pivotal side to side movement of the grading device (120) relative to the direction of travel of the truck thereby enabling the pitch of the grading device (120) to be adjusted.

The fastening plates (320) each have a fastening end (322), which is fastened to the underside of the truck, and a coupling end (324) extending downwardly from the underside of the truck for coupling with the upper part (132) of the coupling mechanism (130). Each coupling end (324) further defines an aperture (326) for receiving a pin to couple the upper part (132) of the coupling mechanism (130) to the underside of the truck thereby forming a hinged joint that allows the coupling mechanism (130) to pivot in a longitudinal direction relative to the truck.

The rotational coupling mechanism (310) includes a lower part (312), which is rotationally coupled to the upper part (314) such that the lower part (312) can rotate relative to the fixed upper part (314). The lower part (312) is pivotally coupled to a rear face of the grader blade (300) such that the inclination of the grader blade (300) can be adjusted. Rotation of the lower part (312) relative to the upper part (314) is facilitated by a ring gear (316) located on the lower part (312), which is rotated by a driven planet gear mechanism (318) operatively associated with the upper part (314).

Movement of the grading device (120) between the operational and stowage positions in this embodiment is facilitated by two linear actuators (330), which are pivotally coupled to the underside of the truck via fastening plates (320) and to opposite sides of the upper part (314) of the rotational coupling mechanism (310). The linear actuators (330) can be pneumatically or hydraulically driven. In use, when the linear actuators (330) are retracted, the grading device (120) is raised to the stowage position. Conversely, when the linear actuators (330) are extended, the grading device (120) is lowered into the operational position.

Advantageously, individual operation of one of the two linear actuators (330), allows the pitch of the grading device (120) to be adjusted via the swivel joint (134).

A single linear actuator (330) pivotally coupled to the rear face of the grader blade (300) at one end and to the lower part (312) of the rotational coupling mechanism (310) at the other end, allows the inclination of the grader blade (300) to be adjusted by extension and retraction of the linear actuator (330).

FIG. 4 shows another embodiment of the grading assembly (100) in which the grading device (120) is in the form of a drag for dragging along the surface of the dirt or gravel road in the direction of travel of the truck (110) for maintaining the surface of the road.

The grading device (120) is indirectly coupled to the underside of the truck (110) via an adjustable carriage assembly in the form of a parallelogram linkage mechanism (400). The parallelogram linkage mechanism (400) facilitates movement of the grading device (120) between the operational position (as presently shown), and the stowage position.

Advantageously, the parallelogram linkage mechanism (400) facilitates in keeping the grading device (120) in a substantially parallel plane with the underside of the truck (110) and the surface of the road.

FIG. 5 shows the embodiment of the grading assembly (100) as shown in FIG. 4 save that the grading assembly (100) is in a non-operational mode in which both the grading device (120) and the compacting roller (140) are in the stowage positions.

Referring to FIG. 6, the grading device (120) includes an upper horizontal panel (600), which is coupled to the parallelogram linkage mechanism (400), and a plurality of scraper blades (610), which extend downwardly from the panel (600) for, in use, scraping and thereby shaping and maintaining the camber or the crown of the dirt or gravel road.

Best shown in FIG. 6, the parallelogram linkage mechanism (400) has two coupling arms (410) that are each pivotally coupled at an upper end to the underside of the truck via fastening plates (320) and at a lower end to an upper surface (605) of the panel (600) of the grading device (120). The coupling arms (410) are longitudinally arranged relative to one another along a length of the underside of the truck. The parallelogram linkage mechanism (400) enables the panel (600) and thereby the grading device (120) to remain substantially parallel with the surface of the road and the underside of the truck when moved between the operational and stowage positions.

Each coupling arm (410) is coupled to the upper surface (605) of the grading device (120) via a coupler (611). Each coupler (611) is configured to allow the grading device (120) to pivot in a longitudinal direction and a lateral direction relative to the coupling arm (410). To achieve this, the coupler (611) includes two sleeves (615) fastened atop one another. Each sleeve (615) is configured to receive a pin to couple the grading device (120) to the coupling arm (410).

An upper sleeve (615 a) is coupled to the coupling arm (410) and is perpendicularly aligned relative to the direction of travel of the truck (as indicated by the arrow). The upper sleeve (615 a) allows longitudinal pivoting of the grading device (120) relative to the coupling arm (410).

A lower sleeve (615 b) is coupled to the upper surface (605) of the panel (600) of the grading device (120) and is axially aligned relative to the direction of travel. The lower sleeve (615 b) allows lateral pivoting of the grading device (120) relative to the coupling arm (410).

In this embodiment, movement of the grading device (120) between the operational and stowage positions is, like with the movement of the roller frame (142) and compacting roller (140) shown in FIG. 1, facilitated by a cable (680) driven by an electric winch (682). The cable (680) is attached to a lower end of a rearmost coupling arm (410) relative to the direction of travel. In use, the electric winch (682) winds in cable (680) to raise the grading device (120) to the stowage position, and lets the cable (680) out to lower the grading device (120) into the operational position.

Referring to FIG. 7, the plurality of scraper blades (610), which extend downwardly from the panel (600), include a first portion (612) of scraper blades (610) arranged parallel to one another, mounted vertically and at an angle relative to the direction of travel (as indicated by the arrow), and a second portion (614) of scraper blades (610) arranged parallel to one another, mounted at an angle significantly inclined from the vertical while trailing away from the direction of travel of the truck, and perpendicularly relative to the direction of travel.

In use, the first portion (612) of scraper blades (610) are arranged to move road material substantially sideways relative to the direction of travel.

In use, the second portion (614) of scraper blades (610), which extend downwardly from the panel (600) at an angle from vertical away from the direction of travel, are arranged to receive and smooth the road material moved by the first portion (612) of scraper blades (610). A last scraper blade (610) of the second portion (614), relative to the direction of travel, extends across an entire width of the panel (600) to smooth any road material disturbed by passage of the first portion (612) of scraper blades (610).

FIG. 8 shows another embodiment of the grading assembly (100) of the present invention in which the grading device (120) is indirectly coupled to the underside of the truck (110) via an adjustable carriage assembly in the form of a single coupling arm (410).

The coupling arm (410) is rotationally coupled to the grading device (120) via a rotating mechanism (800), which allows the grading device (120) to be rotated around its vertical axis relative to the coupling arm (410) to thereby adjust the orientation of the grading device (120).

FIG. 8 also shows another embodiment of the grading device (120) in which the panel (600) has a plurality of scraper blades (610) extending down from the panel (600) for, in use, scraping and thereby grading the surface of the road. Each blade (610) extends across a length of the panel (600) in a substantially parallel arrangement with the other blades (600).

FIG. 9 shows the embodiment of the grading assembly (100) as shown in FIG. 8 save that the grading assembly (100) is in a non-operational mode in which both the grading device (120) and the compacting roller (140) are in the stowage positions.

Best shown in FIG. 10, the rotating mechanism (800) is operatively associated with the upper surface (605) of the grading device (120) with two rollers (805; i.e., rotating members) extending outwards from the rotating mechanism (800) in a direction parallel with the panel (600) of the grading device (120). Each roller (805) is configured to rotate around its central axis and in an opposite direction to the other roller (805) to facilitate rotation of the grading device (120) around its vertical axis. Each roller (805) includes a grip (810; i.e., gripping member) at its distal end for gripping with the upper surface (605) and rotating the grading device (120).

The rotating mechanism (800) can be either manually driven (i.e., by hand) or be driven by an electric motor.

In this embodiment, it is important that the orientation of the grading device (120) is adjustable via the rotating mechanism (800) to, in use, allow road materials to be moved sideways relative to the direction of travel and facilitate in the maintenance of a road's crown or camber.

FIG. 11 shows another embodiment of the grading assembly (100) in which the panel (600; as shown in FIGS. 8 to 10) is indirectly coupled to the underside of the truck (110) via an adjustable carriage assembly in the form of two chains (900) coupled to a forward end of the panel (600) together with a cable (910), which is associated with a moveable pulley (920) coupled to a rear end of the panel (600). The cable (910) is also associated with a winch (925; visible in FIG. 13) and two fixed pulleys (930; visible in FIG. 13), which are all coupled to the underside of the truck (110). In this arrangement, the grading device (120) is moved between the operational and stowage positions in a linear translational movement by action of the winch (925) winding in or letting out the cable (910).

FIG. 12 shows the grading assembly (100) as shown in FIG. 11 save that the grading assembly (100) is in a non-operational mode in which both the grading device (120) and the compacting roller (140) are in the stowage positions.

Referring to FIG. 13, the chains (900), cable (910) and moveable pulley (920) are removably coupled to the upper surface (605) of the panel (600). The upper surface (605) of the panel (600) includes a plurality of apertures (940), each aperture (940) being configured to receive a coupler (950) to couple any one of the chains (900), cable (910) and moveable pulley (920). In this arrangement, an operator can manually uncouple any one of the removably coupled components from the upper surface (605) of the panel (600) and then re-couple the uncoupled component to a different aperture (940) to adjust the orientation of the grading device (120).

FIGS. 14A to 14D show further embodiments of the grading assemblies respectively shown in FIGS. 2, 5, 9 and 12 in which the water dispersal nozzles (112) of the truck (110) are located in front of the grading device (120).

A method of shaping and maintaining a camber or a crown of a dirt or gravel road with the grading assembly (100) is now briefly described.

An operator drives the truck (110) carrying the grading assembly (100) to a stretch of dirt or gravel road requiring maintenance and lowers the grading device (120) and compacting roller (140) to the operational positions. The operator also activates the water dispersal nozzles (112) located at the rear of the truck (110) or in front of the grading device (120) such that water is ejected in a controlled and specified capacity behind the truck (110). The truck (110) is now in an operational mode for shaping and maintaining the camber or the crown for the stretch of dirt or gravel road.

The operator then proceeds to drive the truck (110) slowly along the stretch of road requiring maintenance allowing the grading device (120) to shape and maintain the camber or the crown the road by moving and smoothing road material. Once, the operator reaches the end of the stretch of road, the truck can optionally be turned around for a return passage. This process can be repeated until the road's surface has reached an acceptable standard wherein a majority, if not all, of the depressions in the road's surface have been filled and smoothed together with the remainder of the road's surface and any camber or crown in the road has been restored. This process is more effectively completed after a controlled amount of water has been applied to the surface of the dirt or gravel road, thus making the road material more easily worked and compacted into a durable surface of desired shape.

Once the grading process has been completed, the operator returns the grading device (120) and compacting roller (140) to the stowage positions and deactivates the water dispersal nozzles (112) to put the truck in a non-operational mode for transit of the truck (110) away from the repaired stretch of road.

A person skilled in the art will appreciate that many embodiments and variations can be made without departing from the ambit of the present invention.

For example, in an alternative embodiment, the grading assembly may additionally include GPS navigations means and/or laser levelling means to facilitate in precision grading of the surface of a dirt or gravel road, particularly in the maintenance of a road's crown or camber.

In the present specification and claims (if any), the word ‘comprising’ and its derivatives including ‘comprises’ and ‘comprise’ include each of the stated integers but does not exclude the inclusion of one or more further integers.

Reference throughout this specification to ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art. 

1. A grading assembly adapted for use with a water truck or truck having water dispersal means, said truck having a forward cab from which the truck is operated, said assembly comprising: a grading device configured to be carried by an underside of the truck and positioned between front and rear axles of the truck, said grading device being configured to shape and maintain a camber or a crown of a dirt or gravel road, wherein said grading device is in use operated from the cab of the truck.
 2. The assembly of claim 1, wherein the truck includes a prime mover and a trailer and the grading device is configured to be carried by an underside of the trailer in a position between axles of the prime mover and the trailer.
 3. The assembly of claim 2, wherein the grading device is configured to be positioned between the axles of the prime mover and a forward most axle of the trailer of the truck.
 4. The assembly of claim 1, wherein the grading device is carried indirectly by the truck via an adjustable carriage assembly.
 5. The assembly of claim 4, wherein the adjustable carriage assembly facilitates in movement of the grading device between an operational position in which the grading device can engage with the surface of the dirt or gravel road, and a stowage position in which the grading device is raised and held clear of the surface of the dirt or gravel road.
 6. The assembly of claim 5, wherein the adjustable carriage assembly further facilitates in adjustment of a pitch of the grading device relative to a direction of travel of the truck.
 7. The assembly of claim 6, wherein the adjustable carriage assembly further facilitates in adjustment of an orientation of the grading device relative to a direction of travel of the truck.
 8. The assembly of claim 6, wherein the adjustable carriage assembly is a parallelogram linkage mechanism having at least two coupling arms pivotally coupled to the underside of the truck and to an upper portion of the grading device to facilitate in movement of the grading device between the operational and stowage positions.
 9. The assembly of claim 8, wherein the at least two coupling arms are each coupled to the upper portion via a coupler that allows the pitch of the grading device to be adjusted relative to the direction of travel of the truck.
 10. The assembly of claim 7, wherein the adjustable carriage assembly includes at least one coupling arm pivotally coupled to the underside of the truck and to an upper portion of the grading device to facilitate in movement of the grading device between the operational and stowage positions.
 11. The assembly of claim 10, wherein the grading device is rotationally coupled to the at least one coupling arm such that the orientation of the grading device around its vertical axis relative to the at least one coupling arm is adjustable.
 12. The assembly of claim 7, wherein the adjustable carriage assembly includes at least one chain coupled to the underside of the truck and to an upper portion of the grading device together with a cable, associated with a winch coupled to the underside of the truck, and a moveable pulley associated with the cable such that the grading device is moved between the operational and stowage positions in a linear translational movement by action of the winch winding in or letting out the cable.
 13. The assembly of claim 12, wherein the at least one chain, cable and moveable pulley are removably coupled to the upper portion of the grading device and the orientation of the grading device relative to the truck is adjustable by uncoupling and re-coupling the grading device to the at least one chain, cable and moveable pulley at a desired orientation.
 14. The assembly of claim 1, wherein the grading device comprises a grader blade configured for shaping and maintaining the camber or the crown of the dirt or gravel road.
 15. The assembly of claim 1, wherein the grading device comprises a drag for dragging along the surface of the dirt or gravel road to shape and maintain the camber or the crown of the dirt or gravel road.
 16. The assembly of claim 15, wherein the drag includes an upper substantially horizontal panel and a plurality of scraper blades extending down from the panel for scraping and thereby shaping and maintaining the camber or the crown of the dirt or gravel road.
 17. The assembly of claim 16, wherein the plurality of scraper blades includes a first portion of scraper blades configured to, in use, move road material sideways relative to the direction of travel, and a second portion of scraper blades configured to, in use, smooth road material moved sideways by the first portion.
 18. The assembly of claim 1, further comprising a compacting device configured to facilitate compaction of the surface of the dirt or gravel road.
 19. The assembly of claim 1, wherein the water dispersal means comprises one or more water dispersal nozzles equipped with mechanics to pump water from a water reservoir carried by the truck and disperse water on to the surface of the dirt or gravel road in a controlled and specified capacity.
 20. (canceled)
 21. A grader vehicle for maintenance of a dirt or gravel road, said vehicle being in the form of a truck having a forward cab from which the truck is operated, said vehicle comprising: a grading device configured to shape and maintain a camber or a crown of the dirt or gravel road, said grading device being carried by an underside of the truck in a position between front and rear axles of the truck; and water dispersal means for dispersing water on to the dirt or gravel road, wherein said grading device is in use operated from the cab of the truck.
 22. A method of maintaining a dirt or gravel road with a grading assembly attached to a water truck or truck having water dispersal means, said truck having a forward cab from which the truck is operated, said method comprising: shaping and maintaining a camber or a crown of the dirt or gravel road with a grading device configured to be carried by an underside of the truck in a position between front and rear axles of the truck, wherein said grading device is in use operated from the cab of the truck. 